Update halfshot/matrix-hookshot Docker tag to v7.3.0 (#3324)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [halfshot/matrix-hookshot](https://github.com/matrix-org/matrix-hookshot) | minor | `7.2.0` → `7.3.0` |

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> ⚠️ **Warning**
>
> Some dependencies could not be looked up. Check the Dependency Dashboard for more information.

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### Release Notes

<details>
<summary>matrix-org/matrix-hookshot (halfshot/matrix-hookshot)</summary>

### [`v7.3.0`](https://github.com/matrix-org/matrix-hookshot/blob/HEAD/CHANGELOG.md#730-2026-01-19)

[Compare Source](https://github.com/matrix-org/matrix-hookshot/compare/7.2.0...7.3.0)

#### Features

- Add an optional template argument to the `feed` command, to allow specifying a template for feed entries when using the command interface. ([#&#8203;1097](https://github.com/matrix-org/matrix-hookshot/issues/1097))
- Static connections may now be configured in the config file. ([#&#8203;1102](https://github.com/matrix-org/matrix-hookshot/issues/1102))
- Prefixes are now supported on listeners. You may specify a `prefix` under any `listener` config entry. ([#&#8203;1119](https://github.com/matrix-org/matrix-hookshot/issues/1119))

#### Bugfixes

- Fix a case where outbound webhooks would not work if you had not enabled openproject (due to a mixed up config check). ([#&#8203;1095](https://github.com/matrix-org/matrix-hookshot/issues/1095))
- Fix /oauth responding with 405 despite GitHub being configured. ([#&#8203;1105](https://github.com/matrix-org/matrix-hookshot/issues/1105))
- Ensure running Hookshot with a missing or empty user namespace in the registration file. ([#&#8203;1116](https://github.com/matrix-org/matrix-hookshot/issues/1116))

#### Internal Changes

- Update matrix-bot-sdk / matrix-appservice-bridge to latest versions. ([#&#8203;1120](https://github.com/matrix-org/matrix-hookshot/issues/1120))

</details>

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Reviewed-on: https://gitea.alexlebens.dev/alexlebens/infrastructure/pulls/3324
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
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clusters/cl01tl/helm/matrix-synapse/values.yaml

@@ -143,7 +143,7 @@ matrix-hookshot:
         main:
           image:
             repository: halfshot/matrix-hookshot
-            tag: 7.2.0
+            tag: 7.3.0
             pullPolicy: IfNotPresent
           resources:
             requests: